void Back_Clicked(object sender, EventArgs e)
{
if (MyWebView.CanGoBack)
{
MyWebView.GoBack();
}
}
public override bool OnKeyDown(Android.Views.Keycode keyCode, Android.Views.KeyEvent e)
{
if (keyCode == Keycode.Back)
{
if (MyWebView.CanGoBack())
{
MyWebView.GoBack();
}
return(true);
}
return(base.OnKeyDown(keyCode, e));
}
public MainPage()
{
InitializeComponent();
string CurrentUrl = "https://www.baidu.com/";
_webView = new MyWebView()
{
Source = CurrentUrl,
HorizontalOptions = LayoutOptions.FillAndExpand,
VerticalOptions = LayoutOptions.FillAndExpand
};
BackButton = new Button
{
Text = "Go Back",
BackgroundColor = Color.FromHex("990000"),
TextColor = Color.White
};
grid = new Grid
{
//...
};
grid.Children.Add(_webView, 0, 6, 0, 7);
Content = grid;
checkToShowButton();
//Button click
BackButton.Clicked += OnBackButtonClicked;
void OnBackButtonClicked(object sender, EventArgs e)
{
_webView.GoBack();
checkToShowButton();
if (_webView.CanGoBack == false)
{
grid.Children.Remove(BackButton);
}
}
}
private void Nav_BackRequested(object sender, BackRequestedEventArgs e)
{
// This event handler will occasionally be called twice, so it's important
// to check if we've handled it already
if (!e.Handled)
{
if (MyWebView.CanGoBack)
{
e.Handled = true;
MyWebView.GoBack();
}
else if (this.Frame.CanGoBack)
{
e.Handled = true;
this.Frame.GoBack();
}
}
}
private void back()//后退
{
MyWebView.GoBack();
}
public MainPage()
{
InitializeComponent();
string CurrentUrl = "https://www.baidu.com/";
_webView = new MyWebView()
{
Source = CurrentUrl,
HorizontalOptions = LayoutOptions.FillAndExpand,
VerticalOptions = LayoutOptions.FillAndExpand
};
BackButton = new Button
{
Text = "Go Back",
BackgroundColor = Color.FromHex("990000"),
TextColor = Color.White
};
grid = new Grid
{
VerticalOptions = LayoutOptions.FillAndExpand,
RowDefinitions =
{
new RowDefinition {
Height = GridLength.Auto
},
new RowDefinition {
Height = GridLength.Auto
},
new RowDefinition {
Height = new GridLength(1, GridUnitType.Star)
},
new RowDefinition {
Height = new GridLength(50, GridUnitType.Absolute)
},
new RowDefinition {
Height = new GridLength(15, GridUnitType.Absolute)
},
new RowDefinition {
Height = new GridLength(15, GridUnitType.Absolute)
},
new RowDefinition {
Height = new GridLength(36, GridUnitType.Absolute)
}
},
ColumnDefinitions =
{
new ColumnDefinition {
Width = GridLength.Auto
},
new ColumnDefinition {
Width = new GridLength(1, GridUnitType.Star)
},
new ColumnDefinition {
Width = new GridLength(50, GridUnitType.Absolute)
},
new ColumnDefinition {
Width = new GridLength(50, GridUnitType.Absolute)
},
new ColumnDefinition {
Width = new GridLength(1, GridUnitType.Star)
},
new ColumnDefinition {
Width = GridLength.Auto
}
}
};
grid.Children.Add(_webView, 0, 6, 0, 7);
Content = grid;
checkToShowButton();
//Button click
BackButton.Clicked += OnBackButtonClicked;
void OnBackButtonClicked(object sender, EventArgs e)
{
_webView.GoBack();
checkToShowButton();
if (_webView.CanGoBack == false)
{
grid.Children.Remove(BackButton);
}
}
}